/* SPDX-License-Identifier: BSD-2-Clause */
/**
* @file
*
* @ingroup POSIXAPI
*
* @brief POSIX Function Installs signal Handler
*/
/*
* signal(2) - Install signal handler
*
* COPYRIGHT (c) 1989-1999.
* On-Line Applications Research Corporation (OAR).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <signal.h>
#include <errno.h>
#ifndef HAVE_SIGHANDLER_T
typedef void (*sighandler_t)(int);
#endif
sighandler_t signal(
int signum,
sighandler_t handler
)
{
struct sigaction s;
struct sigaction old;
s.sa_handler = handler ;
sigemptyset(&s.sa_mask);
/*
* Depending on which system we want to behave like, one of
* the following versions should be chosen.
*/
/* #define signal_like_linux */
#if defined(signal_like_linux)
s.sa_flags = SA_RESTART | SA_INTERRUPT | SA_NOMASK;
s.sa_restorer= NULL ;
#elif defined(signal_like_SVR4)
s.sa_flags = SA_RESTART;
#else
s.sa_flags = 0;
#endif
sigaction( signum, &s, &old );
return (sighandler_t) old.sa_handler;
}